narrow, better defined on early whorls, undulating over axials of previous whorl on adult part of shell. Brephic sculpture of axials without spirals, at first broad and rounded, becoming narrow, sharply crested and very widely spaced on later whorls. Whorl angle at first rounded, becoming sharp by about the third whorl where it begins to develop a very weak spiral girdle similar to that of Vexillitra Marwick, which forms small sharp tubercles at the intersections with the axials. The axials diminish across the shoulder, not reaching the sub-sutural fold, and, on the type species, taper downwards, reaching almost on to the fasciole. Spiral sculpture is absent from the shoulder, weak immediately below the whorl angle and on the neck, stronger on the base, consisting of a few distant, low, broad, rounded cords. Sinus, judged from the growth lines, on the lower part of the shoulder, very shallow. Anterior canal short, inner lip very thin, with ill-defined boundary.

Mangaoparia is doubtfully located in the Borsoniinae, close to Awateria The posterior sinus is very similar to that of Awateria, and excepting the sub-sutural fold, the sculpture is not very different from the species A. marwicki Powell, and A. defossa Powell. The lack of the moniliform sub-sutural fold, and the very wide spacing of the axials, however, show that Mangaoparia is widely divergent from Awateria.

Relationship to Guraleus is a second possibility, for the form and sculpture of Mangaoparia approach (though not closely) those of the Australian shells G. flavescens (Angas), G. singletoni Powell, and G. adelaidensis Powell.

Mangaoparia powelli n.sp. (Pl. 27, figs. 26, 27.)

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Most details described in the generic diagnosis above. Spire about 1 1/2 times the height of the aperture and canal. Post-nuclear whorls 4 1/2. Axials 9 per whorl, vertical, narrow, on penultimate whorl and body roughly in line. On body whorl 2 broad low cords, hardly discernible, below keel, 4 narrower and more distinct on the base, below the suture level. Neck with 3 or 4 microscopic cords.

Height, 5.3 mm.; diameter, 2.9 mm.

Locality: N165/507, Bell's Creek, middle Tongaporutuan (holotype and 2 paratypes) (Bell's Creek is a small tributary of Mangaopari Stream).

Antiguraleus rishworthi n. sp. (Pl. 26, fig. 13.)

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Very small, short and broad, spire slightly higher than the aperture plus canal. Strong peripheral carina below a gently sloping very lightly concave shoulder. Axials narrow, moderately high, sharply crested, distant, vertical, 10 on body whorl extending on to neck. Spirals, 5 or 6 very fine threads on the shoulder; a strong cord on the periphery rendering axials tuberculate; a second primary cord mid-way between the keel and the lower suture on spire whorls, forming weak tubercles at the intersections with the axials; 6 more primary cords below the suture level, on the body whorl, becoming weaker on the neck and fasciole; mid-way between each pair of primaries a secondary cord, and in each interspace a tertiary very fine thread. Sinus on the shoulder, U-shaped shallow, but deep for the genus; outer lip broken, but growth-lines showing a slight indentation as though indicating a “stromboid notch”. Anterior canal short, broad. Protoconch of 1 1/2 smooth glossy whorls, the tip small and slightly eccentric.

Height, 4·8 mm.; diameter, 2·9 mm.

Locality: N165/507, Bell's Creek, middle Tongaporutuan. Unique holotype.